1. Field of the Invention
This invention relates generally to cyclone type carbon dioxide snow generators and more particularly to a cyclone type snow generator designed to prevent the buildup of snow in the separation chamber.
2. Description of the Prior Art
In the manufacture of carbon dioxide snow by flashing liquid carbon dioxide, a mixture of the carbon dioxide snow and vapor is created. It is desirable to separate the snow from the vapor, and numerous devices have been developed to accomplish this result. One such device is a cyclone separator which operates by the combined actions of centrifugal force and gravity to separate the snow from the vapor. Such a separator is well known in the art.
A problem which occurs with a cyclone type separator forming snow from liquid carbon dioxide is the buildup of snow on the inside surface of the separator cone as the carbon dioxide expands through the nozzle orifices. Snow builds up on the inside surface of the cone adjacent to the lower discharge end, and the buildup increases until eventually the discharge end of the cone is completely blocked. Additional snow builds up at the upper end of the cone adjacent to the injection nozzles. This snow buildup on the cone wall cause a progressive decrease in the efficiency of the cyclone type separator and eventually the separator ceases to operate. A fresh buildup of snow is difficult to break up because it is held together by a static charge and it is flexible. In order to remove built-up snow by vibrating the cone, the magnitude of the vibrations is so great that the cone is damaged.